The World Wide Web is a major delivery platform for Web development consisting of complex and sophisticated applications with multifaceted functionality and complex behavior. Web development is a broad term for the work involved in developing a website for the Internet (World Wide Web) or an intranet (a private network). Web development can range from developing a static single page of plain text to a complex Web-based Internet application. Each webpage can contain numerous types of information: perceived or rendered (e.g., text, graphics, audio, interactive), internal or hidden (e.g., comments, linked files, metadata, style information, scripts), and adapted information elements (dependent upon the browser or end-user location).
Web testing tools evaluate a designed webpage for scripting requirements, graphical user interface (GUI) functionalities, and/or browser compatibility. Some types of tests or techniques utilized to evaluate a designed webpage are: Data Driven Testing (DDT) (i.e., a test that uses the same test, or tests, multiple times with varying data), database validation (i.e., comparing data in the User Interface (UI) against data stored in a database), functional testing (i.e., checking to ensure a webpage or application responds as anticipated), and layout testing (i.e., a test to determine whether visual aspects of a webpage are correct). Layout testing is a visual comparison of webpages performed by utilizing screenshots. A screenshot is an image taken by recording visible items displayed on a visual output device. Layout testing is achieved by capturing an initial image that is the basis for which subsequent test images are to be compared.